Creating a generic, extensible data block component in Vue

[ml-evs]

cc @BenjaminCharmes -- assigning you to start thinking about this idea, rather than implementing it all yourself!

Essentially, it would be good to build a JS design language for generic blocks, i.e., provide many options to enable multi-file upload, passing arbitrary parameters requested by the schema (or user-specific extensions), handle static plots vs interactive Bokeh plots, and other block interactions that we can reuse everywhere. The Python API can then simply report which features a block implementation needs/can use, so we avoid needing to write a separate vue component per block type.

[ml-evs]

Narrowing this down a bit to a specific task:

let's make a new block abstraction based on DataBlockBase, that can accept a list of properties and their defined types, labels etc.

Example XRD block:

go from hardcoded component in resources.js XRDBlock to DataBlockUI(properties={"wavelength": {"type": "float", "label": "Wavelength (Angstrom)", "default": 1.54}).

Eventually we can return this "block UI schema" from the API and try to generate reasonable block components without the plugin developer needing to write much javascript.